I have just installed ClassicWB_FULL_v28 both on my emulated WinUAE and my real Amiga (A1200 with ACA 1221ec with HDD)

Problem I have is that once I place an icon from e.g Cannon Fodder 2 game folder to workbench by using Leave Out option then Im unable to return this icon back by Put Away. It just sits there on my workbench. I tried Amiga+P and Amiga+L keyboard shortcuts as well.

This happens to me every now and then too. Get rid of it by editing the file .backdrop which will be in the root of one of your disks, just remove the line which has the icon you want to put away and save it, update the screen or reboot and it will be gone.

But usually it should be the job of the Workbench or Scalos to leave out or put away any icons. Icon.library has no function that would handle that. Nothing! And I don't have ClassicWB installed anymore for many years now.